Arnaud Beltrame was already known for his bravery before he willingly took the place of a hostage during a standoff with a rampaging gunman and died of injuries.
The French police officer has been hailed a hero in a country that has been shaken by a number of terrorist attacks over recent years.
Beltrame, 44, was a lieutenant-colonel in the gendarmerie, a part of the French military that focuses on domestic policing.
He had previously been decorated for his bravery during operations in Iraq and spent four years in the early 2000s in France's Republican Guard, protecting the Elysee Palace in Paris.
The Elysee announced that Beltrame would receive a national honour for "giving his life to protect our fellow citizens," according to reports in French media.
"He fell as a hero," President Emmanuel Macron had said earlier, calling on French citizens to honour Beltrame's memory.
"France will never forget his heroism, his bravery, his sacrifice," French Interior Minister Gérard Collomb wrote in a tweet.
According to the Elysee, Beltrame had graduated from France's top military college, Saint-Cyr, in 1999. He was later chosen to join the gendarmerie's elite GSIGN in 2003, and he was deployed to Iraq in 2005. He was married but had no children.
It was only last year that he had been named deputy chief of the gendarmerie in France's Aude department. The French President's office noted that his understanding of counterterrorism had won him appreciation in this position.
Beltrame lost his life while trying to end a standoff police had with a gunman at a supermarket.
Authorities say Radouane Lakdim, 25, hijacked a car near the town of Carcassonne in Aude, killing a passenger and wounding the driver. Lakdim also shot at a group of police officers on their morning jog, wounding one of them. In the nearby town of Trèbes, the gunman then stormed into a supermarket and took hostages.
Beltrame was one of the first officers to respond, authorities said. Police negotiated with Lakdim to release the hostages, and Beltrame offered himself in place of the final one.
Inside the supermarket, Beltrame tried to negotiate with Lakdim. He left his cellphone active on a table to allow authorities outside to listen in. When police heard gunshots, they stormed the building and shot Lakdim, killing the gunman.
Three other people were killed and several others were injured during Lakdim's rampage.
Macron commended the officer, who was then on his deathbed in a hospital: "He saved lives. He is fighting for his life."
In an interview with the local Depeche du Midi newspaper in December, Beltrame described being trained to counter a terrorist attack on a supermarket.
"A mass killing took place in a supermarket. This is the only information that was given to the police," he told the newspaper, according to a translation from Reuters. "We want to be closer to real conditions, so there is no pre-established scenario."
In an interview with RTL radio, Beltrame's mother said she was not surprised he would give himself up for a hostage.
"He has always been like that — someone who, since he was born, was doing everything for his country," said his mother, whose name was not disclosed. "He would say to me: 'I'm doing my job, mum. That's all."
On RTL's website, a poll shows overwhelming support for organising a national honour to Beltrame.